Why take a tight end there instead of addressing a more pressing need, such as quarterback (Geno Smith) or cornerback (Darius Slay, Jonathan Banks) or safety (D.J. Swearinger) or defensive end (Tank Carradine)?
Because they are running this draft by the book, that's why. The best-athlete-available book.
That's why they selected offensive tackle Lane Johnson with the fourth overall pick in the draft on Thursday, and why they selected Ertz with the 35th pick, and why they took LSU defensive tackle Bennie Logan with the 67th pick.
If they ultimately make any mistakes in this draft - and we really won't know that for a while - it will be because they erred in their evaluation of a player, not because they ignored a player with a higher grade to address a need; i.e., pick a name, almost any name in the 2010-11 drafts.
"[Ertz] was at the top of our board," Kelly said matter-of-factly. "We don't want to manufacture things as we go.
"I don't think you can go in and say we need this and we need that. I think when people do that, they get off schedule. You can't force it. In this situation, we had our fingers crossed that our top guy [Ertz] would be there when we got to the third pick [of the round]."
To be perfectly honest, one of the NovaCare maintainance guys could have run this draft for the Eagles the last 2 days. The heavy lifting was done in the weeks and months leading up to the draft when the Eagles scouted and graded all of the prospects and then set up their draft board.
Since Thursday night, it's just been a matter of crossing off the names of players taken by other teams, then picking the top guy left on their board, position be damned. They might've considered trading down in the first three rounds, but said nobody called them.
"We've spent a lot of time and invested a lot of man-hours in the evaluation of this process and we're going to continue to follow [our board]," Kelly said.
"The people that make mistakes are the ones that jump around when they look at it and say, 'Hey, we need this position. So even though this kid has a lower grade, we're going to jump it and go here.'
"When you look at the history of it, when that stuff happens, that's where you make mistakes. You've got to trust the work you've put in to this point and let it unfold the way it unfolds."
So, the Eagles let Smith slide on by at 35 and took Ertz. Smith ended up going four picks later to the Jets. A mistake? Only time will tell.
The Eagles will let their board drive this draft, and if that means not taking a quarterback and going into the 2013 season with Mike Vick, Nick Foles and Dennis Dixon as their three quarterbacks in a yet-to-be-determined order, well, so be it.
Most of the top quarterbacks in the NFL have a first- or high-second-round pedigree. Eight of the 12 starting quarterbacks in the playoffs last season were top-35 draft picks. Ten of the league's top 15 passers also were top-35 picks.
Maybe Vick will get his act together this season (doubtful). Maybe Foles will prove to be a better fit in Kelly's offense than we think (also doubtful).
Maybe the Eagles will take a quarterback in the fourth round (Arizona's Matt Scott? Syracuse's Ryan Nassib?) who will unexpectedly blossom into their quarterback of the future.
Or maybe they'll just wait for the 2014 draft shipment of quarterbacks, when the likes of Louisville's Teddy Bridgewater and Texas A & M's Johnny Manziel and Clemson's Tajh Boyd and Alabama's A.J. McCarron all are expected to be available.
But Kelly and Roseman weren't going to reach for one in the first three rounds of this draft. Which hardly made them unique.
Only three quarterbacks ended up getting taken Thursday and yesterday: E.J. Manuel, who was selected by the Bills in the first round, Smith, and Mike Glennon, who went to Tampa Bay in the third round, six picks after the Eagles selected Logan.
"We're just going to let this unfold the way it is and let the rest of it play itself out," Kelly said. "[Quarterback] obviously is a marquee position and gets a lot of notoriety. But there's also been some really good players picked. We thought of Zach as a first-round pick.
"It's ironic. You look at Aaron Rodgers 8 years ago today. He was sitting [undrafted] in the green room [at the draft in New York] all by himself, and now he just signed a contract making him the richest player in the NFL.
Said Roseman: "We're going to make sure we hit on guys in the order they come off [their draft board]. Going into this draft, I couldn't tell you if we were going to go offense or defense [with a pick], because I didn't know how they were going to come off."
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